Regardless of the result of the next general election, there will be plenty of new faces in parliament before Christmas.
Speaker John Bercow is also stepping aside, ensuring the Commons will sound just as different as it looks when the next parliament is formed.
Before the starting pistol fires on yet another general election campaign, Sky News looks at some high-profile MPs whose absence will be felt in the months and years ahead...
The endless drama provided by the House of Commons since the 2016 referendum has made something of an international celebrity out of Speaker John Bercow.
His bellowing interventions during parliamentary debates have delighted plenty, with some of his most noteworthy moments having gone viral on social media - baffling those unfamiliar with political custom in the UK.
But he has also made controversial decisions about what MPs can and cannot vote on during Brexit debates, frustrating the government of Theresa May and of her successor Boris Johnson.
He announced his resignation in an emotional speech to MPs in September, during which he described his 10 years as Speaker as "the greatest honour of my professional life".
Sir Vince Cable
Few have had a political career of such highs and lows in recent times as Vince Cable.
He was first elected as MP for Twickenham in 1997 and was appointed business secretary when the coalition government was formed in 2010.
His party was largely seen to have been punished for partnering with the Tories by the time of the 2015 election, with a disastrous set of results across the country that saw Sir Vince lose his seat.
The 76-year-old reclaimed it at the 2017 election and became leader of the Lib Dems, but stood down for a second time earlier this year to make way for Jo Swinson and will also now retire as an MP.
Former chancellor and Tory grandee Ken Clarke is the longest-serving male MP in the Commons, having served as the member for Rushcliffe since 1970.
He has also served over 20 years in government - under Margaret Thatcher, John Major and David Cameron.
Despite his long-standing presence in the Conservative Party, he was unceremoniously booted out in September for voting against the government in a bid to prevent a no-deal Brexit.
He later told the BBC that he no longer recognised his party, describing it as "the Brexit Party, re-badged" and also criticising Prime Minister Boris Johnson for assembling "the most right-wing cabinet" in Tory history.
Sir Alan Duncan
Alan Duncan was elected as MP for Rutland and Melton in 1992 and has held the seat ever since.
He became the first openly gay Tory MP when he publicly came out 10 years later, and went on to join the shadow cabinet after the 2005 general election.
David Cameron made him minister of state for international development in 2010 and Theresa May made him minister of state for Europe and the Americas in 2016.
He resigned earlier this year over the chance that Boris Johnson was to become prime minister by winning the Tory leadership election - a contest Sir Alan had withdrawn from before David Cameron won in 2005.
Sir Michael Fallon
The former defence secretary has been a presence in the Commons over the course of the last four decades.
He was Tory MP for Darlington from 1983 to 1992 and has been MP for Sevenoaks since 1997, a tenure which peaked when he was appointed defence secretary by David Cameron in 2014.
Mr Fallon enjoyed a majority of 22,000 at the June 2017 general election and it should remain a safe Tory seat.
However, the low point of his long political career came just a few months after his 2017 success when he resigned as defence secretary after becoming the first ministerial casualty in the Westminster sleaze scandal.
Victory for Justine Greening in Putney in 2005 was the first sign of a revival for the Conservative Party after heavy defeats at the 1997 and 2001 general elections.
She was the first Tory MP elected on the evening and for four years she was also the youngest woman representing the party in the Commons.
Ms Greening served as transport secretary and international development secretary under David Cameron, and was education secretary under Theresa May until a cabinet reshuffle in January 2018.
She has backed calls for a second Brexit referendum and was kicked out of the Conservative Party in September for voting against the government to try and stop no-deal.
Labour MP Kate Hoey has been in parliament since winning a by-election in Vauxhall in 1989.
The 73-year-old went on to serve in the Tony Blair government as minister for sport, but in recent times has been prominent for her vocal backing of Brexit.
Despite representing a constituency that voted more than 78% in favour of Remain, Ms Hooey has been a keen supporter of leaving the EU and has even campaigned alongside Nigel Farage.
She suffered a vote of no confidence from her local party last year, when she was accused of ignoring her constituents over Brexit, and announced she would stand down in July.
The prime minister's brother Jo Johnson quit as a minister and as MP for Orpington in September, citing what he described as an "unresolvable tension" between "family loyalty and the national interest".
Mr Johnson, who has been MP for Orpington for nine years, has repeatedly wrestled with his allegiances since the referendum in 2016.
He voted Remain and has since quit government twice in the space of 10 months.
In November last year, he resigned from Theresa May's administration in protest at the ex-PM's Brexit strategy and to call for a second EU referendum.
Sir Oliver Letwin
Former Tory cabinet minister Oliver Letwin is the name behind an amendment that led to Boris Johnson delaying a vote on his Brexit agreement.
It meant MPs withheld approval of the deal until all the legislation to enact the bill was safely passed, which compelled the prime minister to seek a delay from the EU beyond 31 October.
Mr Letwin said he would stand down after losing the Tory whip for voting against the government to oppose no-deal alongside more than 20 colleagues.
He has stood as MP for West Dorset since 1997.
First elected as MP for Hastings and Rye, Amber Rudd has gone on to become a key figure in successive cabinets under both Theresa May and Boris Johnson.
After serving in the now defunct role of energy and climate change secretary under David Cameron, she was appointed home secretary by Mrs May in 2016.
She quit her job over the Windrush scandal in April 2018, but was back in government just seven months later, replacing the arch-Brexiteer Esther McVey as work and pensions secretary.
She was one of few cabinet secretaries to keep her job following a brutal purge by Mr Johnson, but resigned and gave up the whip in September in protest over his Brexit policy and expulsion of a number of Tory MPs.
Sir Nicholas Soames
The grandson of Winston Churchill - Boris Johnson's political hero - lost the Tory whip after 37 years as an MP for two different constituencies, leading to him announcing he would not stand at the next election.
He joined Mr Clarke, Mr Letwin and other rebels who voted against the government to stop a no-deal Brexit and said it was only the third time he had voted against a Tory administration in nearly four decades.
Sir Nicholas, 71, delivered a scathing speech aimed at the Johnson cabinet after losing the whip, telling MPs: "I want to make clear that I always believed that the referendum result must be honoured, and indeed I have voted for the withdrawal agreement on every occasion that it has been presented to the house.
"Which is more than can be said for my right-honourable friend the prime minister, the leader of the house and other members of the cabinet whose serial disloyalty has been an inspiration for so many of us."
He later regained the whip when the snap pre-Christmas general election was announced.
Former British Army soldier Rory Stewart was considered one of the rising stars of the Conservative Party when he became MP for Penrith and The Border in 2010.
He first entered the cabinet as international development secretary in May 2019 but lasted less than three months and lost the Tory whip for voting against the government to try and block a no-deal Brexit in September.
Just a few months prior he had enjoyed a surprisingly successful run in the Tory leadership election and he has since said he will stand to be the next mayor of London.
That commitment means he will step down from his role as an MP, which has seen him become somewhat infamous for his series of online videos dubbed "Rory Walks".
The full list of MPs stepping down: